package gnu.jemacs.buffer;public class Signal extends RuntimeException{  String name;  Object data;  public Signal(String name, Object data)  {    this.name = name;    this.data = data;  }  public static void signal(String name, Object data)  {    throw new Signal(name, data);  }  public static void signal(String name)  {    throw new Signal(name, null);  }  public static void error(Object data)  {    throw new Signal("error", data);  }  public static void message(String msg)  {    System.err.println(msg);  }  public String toString()  {    if (data == null)      return name;    else      return name+": "+data;  }  public static void checkQuit()  {    if (Thread.interrupted())      throw new gnu.mapping.WrappedException(new InterruptedException());  }}